For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningDoing Your Own Service Work
WARNING
It can be dangerous to work on your vehicle if you do not have the proper
knowledge, service manual, tools, or parts. Always follow owner manual procedures
and consult the service manual for your vehicle before doing any service work.
If doing some of your own service work, use the pro ...
Heated Seats
If available, the controls are on the center stack. The engine must be running
to operate the heated seats.
Press or
to heat the driver or passenger seat
cushion and seatback.
Press the control once for the highest setting. With each press of the control,
the heated seat will change to ...
Installation Procedure
Cut the roof front header panel in corresponding locations to fit the
remaining original panel. The sectioning joint should be trimmed
to allow a gap of one-and-one-half-times the metal thickness at the
sectioning joint.
Create a 50 mm (2 in) backing plate from the unused portion of ...